Qi Weichen, Feng Xiaoreng, Zhang Teng, Wu Hao, Fang Christian, Leung Frankie
Department of Orthopaedics and Traumatology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China.
Yangjiang People's Hospital, Yangjiang, China.
Bone Joint Res. 2021 Nov;10(11):714-722. doi: 10.1302/2046-3758.1011.BJR-2021-0028.R1.
To fully verify the reliability and reproducibility of an experimental method in generating standardized micromotion for the rat femur fracture model.
A modularized experimental device has been developed that allows rat models to be used instead of large animal models, with the aim of reducing systematic errors and time and money constraints on grouping. The bench test was used to determine the difference between the measured and set values of the micromotion produced by this device under different simulated loading weights. The displacement of the fixator under different loading conditions was measured by compression tests, which was used to simulate the unexpected micromotion caused by the rat's ambulation. In vivo preliminary experiments with a small sample size were used to test the feasibility and effectiveness of the whole experimental scheme and surgical scheme.
The bench test showed that a weight loading < 500 g did not affect the operation of experimental device. The compression test demonstrated that the stiffness of the device was sufficient to keep the uncontrollable motion between fracture ends, resulting from the rat's daily activities, within 1% strain. In vivo results on 15 rats prove that the device works reliably, without overburdening the experimental animals, and provides standardized micromotion reproductively at the fracture site according to the set parameters.
Our device was able to investigate the effect of micromotion parameters on fracture healing by generating standardized micromotion to small animal models. Cite this article: 2021;10(11):714-722.
全面验证一种实验方法在为大鼠股骨骨折模型生成标准化微动方面的可靠性和可重复性。
已开发出一种模块化实验装置，该装置允许使用大鼠模型而非大型动物模型，目的是减少系统误差以及分组时的时间和资金限制。通过台架试验来确定该装置在不同模拟加载重量下产生的微动测量值与设定值之间的差异。通过压缩试验测量固定器在不同加载条件下的位移，该试验用于模拟大鼠行走引起的意外微动。采用小样本量的体内初步实验来测试整个实验方案和手术方案的可行性和有效性。
台架试验表明，重量加载<500 g不影响实验装置的运行。压缩试验表明，该装置的刚度足以将大鼠日常活动导致的骨折端之间不可控运动保持在1%应变以内。对15只大鼠的体内实验结果证明，该装置工作可靠，不会给实验动物造成过重负担，并能根据设定参数在骨折部位重复性地提供标准化微动。
我们的装置能够通过为小动物模型生成标准化微动来研究微动参数对骨折愈合的影响。引用本文：2021;10(11):714 - 722。
